2–30
Chapter 2: Board Components
Components and Transceiver Interfaces
Cyclone IV GX FPGA Development Board
August 2015
Altera Corporation
Reference Manual
Table 2–32
lists the capacitor or resistor stuffing option to enable either the PCIe
interface or the HSMC port B interface. The multiplexer capacitors are 0.1
F and the
multiplexer resistors are 0
High-Speed Mezzanine Cards
The development board contains two HSMC interfaces—port A and port B. The
HSMC port A interface supports both single-ended and differential signaling while
the HSMC port B interface only supports single-ended signaling. The HSMC interface
also allows JTAG, SMB, clock outputs and inputs, as well as power for compatible
HSMC cards. The HSMC is an Altera-developed open specification, which allows you
to expand the functionality of the development board through the addition of
daughtercards.
f
For more information about the HSMC specification such as signaling standards,
signal integrity, compatible connectors, and mechanical information, refer to the
High
Speed Mezzanine Card (HSMC) Specification
manual.
The HSMC connector has a total of 172 pins, including 120 signal pins, 39 power pins,
and 13 ground pins. The ground pins are located between the two rows of signal and
power pins, acting both as a shield and a reference. The HSMC host connector is
based on the 0.5 mm-pitch QSH/QTH family of high-speed, board-to-board
connectors from Samtec. There are three banks in this connector. Bank 1 has every
third pin removed as done in the QSH-DP/QTH-DP series. Bank 2 and bank 3 have
all the pins populated as done in the QSH/QTH series.
The HSMC port A interface has programmable bi-directional I/O pins that can be
used as 2.5-V LVCMOS, which is 3.3-V LVTTL-compatible. These pins can also be
used as various differential I/O standards including, but not limited to, LVDS,
mini-LVDS, and RSDS with up to 17 full-duplex channels. The HSMC port B interface
is translated from 1.8 V (on the FPGA) to 2.5 V (on the HSMC connector) using a
bidirectional voltage translator.
1
As noted in the
High Speed Mezzanine Card (HSMC) Specification
manual, LVDS and
single-ended I/O standards are only guaranteed to function when mixed according to
either the generic single-ended pin-out or generic differential pin-out.
Table 2–32. Multiplexer Location for PCIe Interface and HSMC Port B Interface
Selection
Multiplexer Location
PCIe interface
Populate C324, C326, C328, C330, C341, C343, C345, C347, R80,
R81, R84, R86, R88, R89, R92, R96
HSMC port B interface
Populate C323, C325, C327, C329, C340, C342, C344, C346, R82,
R83, R85, R87, R90, R91, R93, R97